In current trend, it requires that the furniture is multi-functional. For example, a desk can be converted into a chair or a chair can be converted into a desk. That is the desk and chair are interchangeable.
In one prior art about the desk and chair interchangeable device, each handle of a chair is hidden with a plate. When the plates are taken out from the handle and extend to a horizontal position, the chair can be converted into a chair. However the plate is extended outwards or forwards. As a result it is possible that the center of gravitation will be unstable. Furthermore, the plate is too smaller to be suitable in use. Thereby if the chair has no handle, the plate cannot be installed at a proper position.
In U.S. Pat. No. 1,513,651 and U.S. Application with Publication No. 2004/019730A1, desk and chair interchangeable devices are disclosed. In those disclosures, the back of the chair and seat of the chair are pivotally connected. The back and seat can be rotated to horizontal position so as to be as a desk. Although these are referred design, but no drawer is designed.